Abstract: Genetic diversity of 66 cultivated ancient tea plants from Woshui, Huanglian and Dalong of Liannan was studied based on 24 leaf phenotypic characters such as leaf length, leaf width, leaf area, leaf shape, leaf lamina, leaf margin and so on, the method of variable coefficient, Shannon-Weaver and cluster analysis were used. The results showed that the average variable coefficient of the 66 cultivated ancient tea plants was 31.86%, and the variable coefficient of phyllopodium was the maximum (92.90%), while that of the angle between lateral vein and main vein was the minimum (12.02%). The average Shannon-Weaver index was 1.10, and the diversity coefficient was great. The diversity coefficient of phyllopodium was the maximum (2.08), and that of leaf area was the minimum (0.59). Furthermore, the 66 cultivated ancient tea plants were clustered into 5 groups at the euclidean of 20 based on 24 leaf phenotypic characters, which showed rich variation degree and genetic diversity.